# Sign\_and\_send\_pubkey: signing failed for RSA "(none)" from agent: agent refused operation
**URL:** https://support.nitrokey.com/t/sign-and-send-pubkey-signing-failed-for-rsa-none-from-agent-agent-refused-operation/7654
**Category:** Nitrokeys
**Created:** [June 19, 2026, 11:14am UTC](https://support.nitrokey.com/t/sign-and-send-pubkey-signing-failed-for-rsa-none-from-agent-agent-refused-operation/7654 "2026-06-19T11:14:33Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@kalkat12](https://support.nitrokey.com/u/kalkat12)
#### Post date: [June 19, 2026, 11:14am UTC](https://support.nitrokey.com/t/sign-and-send-pubkey-signing-failed-for-rsa-none-from-agent-agent-refused-operation/7654/1 "2026-06-19T11:14:33Z")
Hi ! For some reason I can’t get SSH to work on my nitrokey 3. With the same secret subkey, when I import it to my PC, SSH works perfectly and I had no problems with it in the past.
If I delete it from my PC with `gpg --delete-secret-keys DAD67EAC40369ABD!` (the key is on nitrokey), then it doesn’t work anymore.
Running `ssh -vT git@github.com` gives me a log and in the end:
```auto
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: get_agent_identities: agent returned 1 keys
debug1: Will attempt key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
debug1: Will attempt key: /home/mantas/.ssh/id_rsa
debug1: Will attempt key: /home/mantas/.ssh/id_ecdsa
debug1: Will attempt key: /home/mantas/.ssh/id_ecdsa_sk
debug1: Will attempt key: /home/mantas/.ssh/id_ed25519
debug1: Will attempt key: /home/mantas/.ssh/id_ed25519_sk
debug1: Offering public key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
debug1: Server accepts key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
sign_and_send_pubkey: signing failed for RSA “(none)” from agent: agent refused operation
debug1: Trying private key: /home/mantas/.ssh/id_rsa
debug1: Trying private key: /home/mantas/.ssh/id_ecdsa
debug1: Trying private key: /home/mantas/.ssh/id_ecdsa_sk
debug1: Trying private key: /home/mantas/.ssh/id_ed25519
debug1: Trying private key: /home/mantas/.ssh/id_ed25519_sk
debug1: No more authentication methods to try.
```
I tested the nitrokey works fine with GPG decryption.
I don’t get a prompt to enter the PIN or anything.
That being said, if the Nitrokey is not connected to my PC and I run this ssh command, then it will ask me to insert this key with ID … If I insert and confirm, I get the same result.
When I import the subkey to my PC (and everything works), this is what `ssh -vT git@github.com` gives me (end):
```auto
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: get_agent_identities: agent returned 1 keys
debug1: Will attempt key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
debug1: Will attempt key: /home/mantas/.ssh/id_rsa
debug1: Will attempt key: /home/mantas/.ssh/id_ecdsa
debug1: Will attempt key: /home/mantas/.ssh/id_ecdsa_sk
debug1: Will attempt key: /home/mantas/.ssh/id_ed25519
debug1: Will attempt key: /home/mantas/.ssh/id_ed25519_sk
debug1: Offering public key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
debug1: Server accepts key: (none) RSA SHA256:F3HmbEtjXq+rnFQTeFQdtm8DHfKfGElEf/HtuzSNpY0 agent
ASKS PASSWORD -----------------
Authenticated to github.com ([140.82.121.4]:22) using "publickey".
debug1: channel 0: new session [client-session] (inactive timeout: 0)
debug1: Entering interactive session.
debug1: pledge: filesystem
debug1: client_input_global_request: rtype hostkeys-00@openssh.com want_reply 0
[...]
```
I have read through the [docs](https://docs.nitrokey.com/nitrokeys/features/openpgp-card/ssh/) and did all of the stuff there and [here](https://bbs.archlinux.org/viewtopic.php?id=245860)
Why does it work when the subkey is on my PC but not when it’s on my nitrokey ? How do I debug further?
---
### Author:  [@kalkat12](https://support.nitrokey.com/u/kalkat12)
#### Post date: [June 25, 2026, 7:44pm UTC](https://support.nitrokey.com/t/sign-and-send-pubkey-signing-failed-for-rsa-none-from-agent-agent-refused-operation/7654/2 "2026-06-25T19:44:35Z")
Solved it.
Created a new key only for authentication and added it to the auth slot on Nitrokey. The previous key was on the encryption slot since I used to have 1 key for both encryption and auth. Everything works now… 🤦♂️
Feel like this should be noted somewhere in the documentation? That the key has to be with auth capabilities and in auth slot on nitrokey for SSH to work.